The present invention relates to a system for detecting the orientation of articles, for example, for detecting the positions or directions of workpieces being transported on a conveyor in a manufacturing factory relative to the direction of transport.
It is necessary to detect the orientation or bearings of workpieces on a conveyor in an automated system in which the workpieces are picked up by the manipulator of a robot because if the workpieces are sent forward as positioned in random directions, the manipulator fails to grasp the workpiece properly unless directed in accordance with the position of the workpiece.
Conventionally the orientations of articles were detected by picking up the color density pattern, color distribution or the like of the article by a camera and checking the resulting image by a pattern recognition technique with reference to a large number of reference patterns stored in a memory. However, this method involves the problem of necessitating storage of reference patterns for all orientations in a memory having a large capacity and requiring a long period of time for pattern checking.